Atmospheric Pressure

Q.

The normal atmospheric pressure is 76 CM of mercury. Calculate the pressure in SI units. Density of Hg = 13600 kg/m3 g =10

Q. A mercury barometer has a column height of $76cm$. What will be the height of the column if the mercury is replaced with an oil having a density of $760kg{m}^{-3}$? (Density of mercury is $13600kg{m}^{-3}$)​

1. $13.6m$
2. $27.2m$
3. $76cm$
4. $23.8m$

Q.

Explain atmospheric pressure in terms of bar?

Q.

What is meant by the statement 'the atmospheric pressure at a place is 76 cm of Hg'? State its value in Pa.

Q.

A barometer kept in an elevator reads $76cm$ when the elevator is accelerating upwards. The most likely pressure inside the elevator (in $cmofHg$) is

Q.

Why it is not allowed to take gel pen in aeroplane.

Q.

The normal atmospheric pressure is

1. 76 m of Hg

2. 76 cm of Hg

3. 76 mm of Hg

4. 76 Pascal

Q.

Find the tension in the string?

1. (m1+m2)g/m1m2

2. 2(m1+m2)g/m1

3. (m1m2)g/(m1+m2)

4. 2(m1m2)g/(m1+m2)

Q.

Why do deep-sea divers wear special suits?

Q.

In the experiment given below, if the atmospheric pressure is 76 cm of Hg $\left(h_0\right)$ and the height is 3 cm, find the pressure of the gas in the tube.

1. 79 cm of Hg

2. 75 cm of Hg

3. 73 cm of Hg

4. 76 cm of Hg

Q.

We do not feel uneasy even under the enormous pressure of atmosphere above as well as around us. Give a reason.

Q.

The atmospheric pressure is 105 N m-2 and density of water is 103 kg m-3. Find the depth of water at which pressure is double than atmospheric pressure.

1. 10 m

2. 100 m

3. 1000 m

4. 0.1 m

Q.

The pressure inside the bottle increases when the bottle is pressed and released.

1. True

2. False

Q.

Why is water not used as a barometric liquid? Give three reasons.

Q.

Name the physical quantity which is expressed in the unit 'atm'. State its value in pascal.

Q.

Describe an experiment to demonstrate that air exerts pressure.

Q.

Why the size of weather balloons increases as it ascends to higher altitudes?

Q.

1. Estimate the fall in height of the mercury column when the barometer is taken from sea level to a hill top of altitude $1.0km$. For this rough estimate take the density of mercury to be $13000kg{m}^{-3}$ and the density of air to be $1.3kg{m}^{-3}$. Assume the densities remain the same at such low altitude.
2. If the barometer reading at sea level is 760 mm of mercury, what is the reading at the hill top?

Q.

The normal atmospheric pressure is :
(a) 76 m of Hg (b) 76 cm of Hg
(c) 76 Pa (d) 76 N $m^{-2}$

Q.

What do you understand by atmospheric pressure?

Q. Why do leaves fall due to the wind?

Q.

A balloon filled with helium gas floats in a big closed jar which is connected to an evacuating pump. What will be your observation, if air from jar is pumped out ? Explain your answer.

Q.

Atmospheric pressure at a place is 650 my of Hg. Calculate the pressure in pascals. Density of Hg = 13600 kg/m3, g = 10

Q. In Barometer , the weight of the column in the tube is equal to the force applied on it by the mercury in the bowl due to atmospheric pressure.

1. True
2. False

Q.

At sea level, the average atmospheric pressure is equal to 76 cm of Hg.

1. True

2. False

Q.

What happens to the barometric height if a faulty barometer is pushed down into the mercury trough?

1. The height will increase

2. The height will decrease

3. The height cannot be determined

4. The height will neither decrease nor increase

Q.

The fluid pressure of atmosphere is measured in ___________. This is equivalent to _________ Pascal.

1. bars, 100 pascals

2. bars, 101, 300 pascals

3. bars, 100000 pascals

4. bars, 300 pascals

Q.

Write the numerical value of the atmospheric pressure on the surface of the earth in pascal.

Q.

Ganesh constructs a barometer. However, instead of mercury, he places another fluid in it. He observes that at normal atmospheric pressure, the height of the liquid column is 7.04 m.

What is the density of the liquid used?

1. 1427.95 kg m⁻³

2. 1405.96 kg m⁻³

3. 1491.98 kg m⁻³

4. 1468.29 kg m⁻³

Q.

when we suck out air from an empty tetra pack of frooti the pack gets crushed? why.